lol :o ...

どうも僕の忠告を無視したようですね、alanXさん。
人をあざ笑う前に自分の日本語を磨き上げること…

Alanx, you keep on laughing at other people but your own Japanese is pretty pathetic.

No your understanding is a bit off.

を is a marker for an object.
が is the marker for the subject.

Example:
I open the door.
I = Subject, Door = Object, Open = Action (transitive).
私が　ドアを　開けます。
Note が is marking 私 as the subject, を is marking ドア as the object. Had it been 私を　ドアが　開けます, it would have meant The door opened me. Which.. could not make much sense but you see the difference.

私が　日本語を　話します
Means I (subject) speak (verb) Japanese (object).

分かります is one of those weird Japanese verbs which has no 100% English equivalent. Just use が when using 分かります. To understand the difference, you have to understand Intransitive Verbs and Transitive Verbs and their use in Japanese (which is slightly different to Vi and Vt in English).

You've never heard me speak Japanese, so how would you know it's pathetic?
And I wasn't laughing at anyone. It's just more practical for someone to look this question on google, instead of making a thread about it.

How about 日本語が出来ますか? I noticed that Japanese people use more the potential form of verbs (also faster I might say), but I love using the potential form of する much more :)

Correction: I personally don't use that phrase but there is nothing wrong with it and I have heard people using it but not as common.

Alternatively, you can say 日本語を話すことが出来ます。

All these are correct, but I still think the most commonly said is just nihongo wo (wo is optional) hanashimasu ka

日本語を話したか does not make too much sense. It kinda means, did you speak (to someone in the past) Japanese. Not denoting ability.

I meant hanasu



I've had a tat bit to drink. :confused: